List of confirmed characters not from GBA FE:
- Lena
- Julian
- Maria
- Minerva
- Cain
- Radd
- Xane (I've got plans for him)
- Alvis
- Azel
- Salem
- Saias
- Kieran
- Shinon
- Subaki
This isn't an exhaustive list, just a quick list of things so far. No, Marcia's not in, she's definitely pink, not red.
E - did a rough list of more characters in this here https://pastebin.com/7VUPXVcf